On Thu, Oct 20, 2016 at 10:44 AM, Viresh Kumar viresh.kumar@linaro.org wrote:
Hi,
Some platforms (like TI) have complex DVFS configuration for CPU devices, where multiple regulators are required to be configured to change DVFS state of the device. This was explained well by Nishanth earlier [1].
Some thoughts went into it few months back but then it all got lost. I am trying to get that back on track with this thread.
One of the major complaints around multiple regulators case was that the DT isn't responsible in any way to represent the ordering in which multiple supplies need to be programmed, before or after frequency change. It was considered in this patch and such information is left to the platform specific OPP driver now, which can register its own opp_set_rate() callback with the OPP core and the OPP core will then call it during DVFS.
The patches are tested on Exynos5250 (Dual A15). I have hacked around DT and code to pass values for multiple regulators and verified that they are all properly read by the kernel (using debugfs interface).
Though more testing on real (TI) platforms would be useful.
This is rebased over: linux-next branch in the PM tree.
V1->V2:
- Ack from Rob for 1st patch
- Moved the supplies structure to pm_opp.h (Dave)
- Fixed an compilation warning.
I need somebody from the OPP camp to review patches [2-8/8] for me.
Thanks, Rafael